设计模式之享元模式

class Program
{
    static void Main(string[] args)
    {
        FlyweightFactory flyweightFactory = new FlyweightFactory();
        IFlyweight black1 = flyweightFactory.GetFlyweight("黑键");
        IFlyweight black2 = flyweightFactory.GetFlyweight("黑键");
        IFlyweight wirte1 = flyweightFactory.GetFlyweight("白键");
        IFlyweight wirte2 = flyweightFactory.GetFlyweight("白键");
        black1.operation(new UnFlyweightObj("1:2"));
        black2.operation(new UnFlyweightObj("10:20"));
        wirte1.operation(new UnFlyweightObj("100:200"));
        wirte2.operation(new UnFlyweightObj("1000:2000"));
    }
}
/// <summary>
/// 非享元角色（也就是享元对象中的区别部分）
/// </summary>
class UnFlyweightObj
{
    // 保存每个对象的个性化信息
    public string Info { get; set; }
    public UnFlyweightObj(string info)
    {
      this.Info = info;
    }
}
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    //抽象享元角色
interface IFlyweight
{
    void operation(UnFlyweightObj state);
}
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/// <summary>
/// 具体享元角色
/// </summary>
class Flyweight : IFlyweight
{
    private string key;
    public Flyweight(string key)
    {
        this.key = key;
        Console.WriteLine($"具体享元{key}被创建");
    }
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    public void operation(UnFlyweightObj state)
    {
        Console.WriteLine($"具体享元{key}被调用");
        Console.WriteLine($"非享元信息是{state.Info}");
    }
}
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/// <summary>
/// 享元角色工厂
/// </summary>
class FlyweightFactory
{
    //存放每个享元对象
    private Dictionary<string, IFlyweight> flyweigths = new Dictionary<string, IFlyweight>();
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    public IFlyweight GetFlyweight(string key)
    {
        IFlyweight flyweight =null;
        bool result = flyweigths.TryGetValue(key, out flyweight);
        if (result)
        {
            Console.WriteLine($"具体享元{key}已经存在，该对象已被复用");
        }
        else
        {
            flyweight = new Flyweight(key);
            flyweigths.Add(key,flyweight);
        }
        return flyweight;
    }
}